package string;

public class StringBuilderDemo {
    public static void main(String[] args) {
        StringBuilder builder1=new StringBuilder();
        StringBuilder builder2=new StringBuilder();

        String str="abc";
        StringBuilder builder3=new StringBuilder(str);
        String str2=builder3.toString();

        String a="好好学习java";
        StringBuilder builder=new StringBuilder(a);//复制内容到builder中

        //append();追加内容-在末尾追加
        builder.append("，为了找个好工作");
        System.out.println(builder);

        //replace();替换部分内容，含头不含尾
        builder.replace(9,16,"就是为了改变世界");
        System.out.println(builder);

        //delete();删除部分内容，含头不含尾
        builder.delete(0,8);
        System.out.println(builder);

        //insert();插入内容
        builder.insert(0,"活着");
        System.out.println(builder);


    }
}
